复合垂直流人工湿地的脱氮机理及影响因素分析

采用沸石和砾石作为填料,研究复合垂直流人工湿地处理农村生活污水的脱氮机理。试验结果表明:复合垂直流人工湿地对污水中氮的去除主要发生在下行流填料柱中,其去除机理主要是微生物对溶解态氮的硝化和反硝化作用;悬浮态氮沉积在填料孔隙中,会出现氮释放现象;水温、气水比、碳氮比、氮源形式等因素对湿地系统的脱氮效率有显著影响。     

约翰内斯堡工艺的工程实践

通过监测城市污水处理厂约翰内斯堡工艺脱氮除磷各处理单元实际运行情况,分析该工艺实际运行效果,探讨该工艺中溶解氧(DO)、污泥龄(SRT)、碳源等因素对系统脱氮除磷效果的影响。     

Relation of lead adsorption on birnessites with different average oxidation states of manganese and release of Mn^2＋/H^＋/K^＋

The characteristics of Pb2+ adsorption on the surface of birnessites with different average oxidation states (AOS) of Mn, synthesized under acidic and alkali conditions, were investigated. The results indicated that the amount of adsorbed Pb2+ increased with the increase of Mn AOS in birnessites. The amount of Pb2+ adsorbed positively correlated with the amount of released Mn2+, H+, and K+ (r = 0.9962 > 0.6614, n = 14, α = 0.01). The released Mn2+, H+, and K+ were derived mostly from the corresponding catio...     

长江口水体中PAHs的基本生态风险特征

通过对2007年4月24—30日采集于长江口水体7个不同采样点18个水样中的4种典型多环芳烃类化合物(PAHs)的浓度分析,依据3个基础营养级水平(藻、、鱼)的毒性效应〔L(E)C50和NOEC〕,采用欧盟适用于现有化学物质与新化学物质的风险评价技术指南(TGD)中的商值法对长江口水体中的萘、菲、蒽、荧蒽进行了生态风险评价. 结果表明,4种PAHs除蒽外的环境浓度/无影响浓度(PEC/PNEC)都小于1. 说明长江口水体中4种PAHs只有蒽存在一定生态风险,其他3种均未对长江口生态造成威胁.      

生态补偿研究现状与进展

回顾和总结了国外生态补偿理论研究和实践发展状况,指出为我国建立生态补偿机制的借鉴作用,分析了我国生态补偿研究现状和实践进程。得出我国生态补偿在理论和实践层面还有需要加强和完善之处,最后提出我国生态补偿研究的主要方向。     

Yield response of potato to spatially patterned nitrogen application

Although crop response to nitrogen fertilization has long been studied, classical experimental designs have led to inadequate accounting of spatial variability in field properties and yield response. Analytical methods to explicitly account for spatial variability now exist but the complementary modification of experimental design is still developing. There is a need to combine these analytical methods with non-traditional experimental design. A 2-year study was implemented to assess the response of potato (Solanum tuberosum cv. Kennebec) yield to nitrogen fertilizer rate. We used a transect-type plot design where four nitrogen treatments (0, 56, 112, and 280 kg N ha^?1) were applied systematically in a continuous sinusoidal pattern along longitudinal transects. Measured field properties included topography, soil texture, pre-application soil nitrate levels, and plant available soil water content. A random field linear model was used to simultaneously account for treatment effects and soil properties. The results showed that treatment effects were significantly different from each other; however, if spatially correlated errors were accounted for, these differences were smaller and significance levels lower. Nitrogen response functions varied widely throughout the field. Of the covariates, only clay content proved important in explaining spatial differences in response to N. The sinusoidal response pattern of N was similar over the 2 years but the amplitudes varied due to differences in weather. Interactions between uncharacteristically high rainfall and a sandy field soil may have minimized discernable effects of the other covariates. The results demonstrated how the statistical analysis of potato response to a patterned application of nitrogen fertilizer can take advantage of spatial correlations to understand the response of potato to nitrogen application over larger areas.     

复合人工湿地系统对生活污水的净化效果

将垂直流人工湿地与水平流人工湿地组成复合人工湿地系统,研究了此复合系统对化粪池出水的净化效果。结果表明,当水平流人工湿地的水力停留时间为3d天时,复合系统对COD、BOD5、TP的去除率分别达到73％、66％、87％,并通过垂直流湿地的硝化作用及水平流湿地的反硝化作用,复合系统对TN的去除率达到40％以上。     

天津港运输船舶大气污染物排放清单

运输船舶产生的大气污染物对港口大气环境有重要影响,但我国对这部分内容的研究却相当薄弱.本文首先对天津港运输船舶的总体情况进行调研,根据其排放控制技术水平合理选择了排放因子;而后采用基于燃料消耗的方法,对2006年天津港运输船舶排放的NOx、HC、CO和PM_(10)进行了计算,建立了天津港运输船舶大气污染物的排放清单;最后对2010年和2020年天津港的运输船舶大气污染排放情况进行了预测.该清单的估算和预测可以为加强排放控制和制定相关法规提供重要依据.     

海水中痕量元素测定及其在重金属污染源判别方面的应用

利用电感耦合等离子体质谱(ICP-MS)研究了胶州湾及莱州湾这两个海域中痕量元素污染水平,发展了ICP-MS海水环境中痕量元素的测定方法,同时找出海水环境中具有保守性的数种元素作为污染示踪元素.达到对于海水环境中痕量污染物被动示踪的目的.对18个真实样品进行了识别率试验,识别率可达90%以上,在选取3个海水样品及1个河水样品混合后的模拟分担率实验,也取得了满意的结果,其误差平均值仅有1.17%.